510 - Muscle strength, lung function and physical capacity in very-to-moderate preterm-born children compared with full-term from a public hospital in Southern Brazil

Poster Number: 510
Publication Number: 510.1103

Background: Preterm birth is known to be associated with reduced physical capacity, which is considered as an independent risk factor of cardiovascular and pulmonary diseases.

Objective: This study aims to investigate muscle strength, lung function and physical capacity in extremely-to-moderate preterm-born school-aged children with full-term children.

Design/Methods: This observational study was conducted on a cohort of preterm-born children ≤32 weeks GA and/or < 1500g, born in a university hospital between 2008-2013. Preterm participants were categorized into 2 groups: extreme (E-PTM, < 28 w. GA) and very-to-moderate (29-33 w. GA, VM-PTM). Full-term children from the same institution were recruited as a control. Study approved by REB 190571. Assessments included clinical examination, body composition, lung function (Datospir MicroC; GLI), maximal Inspiratory Pressure (IPmax, analogic manovacuometer), handgrip strength (dominant hand, digital dynamometer), and Six Minute Walk Test conducted in a one-day visit at Research Center. Groups were compared using One-way Anova (post hoc Bonferroni) and Pearson’ correlation.

Results: A total of 69 preterm children (11±1 y-old: 24 E-PTM: 10 Boys/14 Girls, 143±8 cm, BMI z-score 0.18±1.7 and 45 VM-PTM: 21 B/24 G, 147±9 cm, BMI 0.24±1.3) were significantly lighter when compared with 62 full-term children (11±1 y-old, 34 B/28 G, 148±9 cm, BMI z-score 1.01±1.6). Handgrip strength (Kg) was reduced in E-PTM (13.9±3.8) when compared to Full-term (17.0±4.5), but not with VM-PTM (16.3±4.5) (F(2,127)=3.951; p=0.022). IPmax (cmH2O) was reduced in E-PTM (-76±23) compared to Full-term (-90±19), but not with VM-PTM (-80±23) (F(2,126)=3.745; p=0.026). Both PTM groups presented reduced FEV1 and FEF25-75 when compared to Full-term (F(2,106)=7.797; p=0.004); F(2,106)=4.312; p=0.016, respectively). Walk distance did not differ between groups. Strength of upper limb and inspiratory muscles were strongly correlated with higher lung function in all groups, except IPmax in the E-PTM. Bronchopulmonary dysplasia (37% E-PTM, 13% VM-PTM) and brain lesion (PIVH/leukomalacia; 46% E-PTM, 16% VM-PTM) did not impact in the functional results, except handgrip strength that was reduced PTM with brain lesion.

Conclusion(s): Preterm children in our population, mainly those born < 28 weeks GA, exhibited reduced muscle strength and respiratory capacity, both predictors of long-term morbidity and mortality in adults. These reduced functions may be mitigated by enhancing muscle strength, suggesting that healthcare practitioners should consider incorporating strength-building interventions into follow-up programs.